What's the volume of this liquid? We must take into account both the meniscus and significant digits. Since you always read from the bottom of the meniscus, we know that the volume is between 35 and 40 mL. Then, since the graduations on the cylinder are only every 5 mL, you estimate the last digit; above, I would estimate the volume to be 36 mL (not 36.4, or anything, since the cylinder isn't that precise).